Preparation of Starch Graft Copolymers: Influence of Several Parameters on Structure and Properties

Samples of starch-g-polyacrylonitrile were prepared using the Ce4+ion as initiator. We discuss the influence of the origin of the starch on the polyacrylonitrile content of the copolymer, on the frequency of the grafted chains, and on the molecular weight of the graft. Relations between alkaline hydrolysis conditions and liquid absorption were also studied. The retention increases with the molecular weight of the grafted polyacrylonitrile, and this factor depends on the origin of the starch. Higher absorptions were obtained with low amylose content samples. An absorption maximum was observed that depends on the time of hydrolysis and consequently on the carboxylate group content.